The relationships among Leishmania infantum and phyllostomid bats assessed by histopathological and molecular assays.

Bats have been reported as reservoir host of Leishmania spp. worldwide, mostly by molecular detection. However, it is still unclear whether bats act as reservoirs of Leishmania infantum to sandflies vectors. In this sense, the investigation of amastigotes forms in the target organs, and the characterization of their associated inflammation, may help to clarify the epidemiological importance of bats in endemic areas for leishmaniasis. The aim of this work was to investigate the host-parasite relationships under microscopic evaluation and predict the epidemiological role of two phyllostomid bats species naturally infected by L. infantum in an endemic area for human leishmaniasis. Fragments of skin, liver and spleen of L. infantum positive and negative bats (Artibeus planirostris and Carollia perspicillata) by qPCR, were studied by histological and immunohistochemical techniques. Both groups, positive and negative, did not show differences in the histopathological study, presenting only discrete tissue changes. Liver and skin showed mild inflammatory reactions. Findings on spleen consisted of reactivity of the lymphoid follicles, expressive presence of apoptotic cells and macrophages containing abundant phagocytic cells debris. We did not find amastigote forms in tissues by histological and IHC techniques in positive qPCR bats. Our results allow us to hypothesize that phyllostomid bats seem to have an important role in reducing the risk of transmission, possibly acting as dead-end host.

Establishment of a new equation to estimate gestational age in female dogs.

The objectives of this study were to propose a statistical model to predict the behaviour of the thickness of the uteroplacental junction as a function of the gestation period in female dogs and to determine the relationship between the thickness of the placenta and gestational age in healthy female dogs whose pregnancies had elapsed without maternal-fetal alterations. Eight Border Collie female dogs were selected, aged 3-6 (4.48 ± 0.89) and weighing 16-22 kg (19.06 ± 1.9 kg). Female dogs with gestational ages from 20 to 62 days were examined weekly using B-mode ultrasonography. Ultrasound measurements of the uteroplacental junction were organized into four distinct groups: GT1 (27-36 days of gestation), GT2 (37-46 days of gestation), GT3 (47-56 days of gestation) and GT4 (57-62 days of gestation). Based on multiple linear regression, a statistical model was proposed to predict the behaviour of the thickness of the uteroplacental junction (y) as a function of the length of gestation (x) in female dogs, where b0 is the intercept (linear coefficient) and bp is the slope of the predictors. The analysis relating GT, age and weight could predict placental thickness and resulted in a statistically significant model [F(1,28) = 153,736; p < .001; R2 = .846], but only that relating the length of pregnancy (ß = .92; t = 12.399; p < .001) predicted the thickness of the placenta according to the equation y = b0 + bp.x1 [(thickness in cm) = ß -0.3 + 0.019 × (gestation time in days)]. Only in GT4 was there no correlation between placentas within the same pregnancy (p > .05). Based on the close relationship between the development of the uteroplacental junction thickness during pregnancy and gestational age, it is possible to develop a new tool to complement gestational ultrasound evaluation in female dogs. This is important because it allows better placental evaluation in the search for significant alterations that could compromise maternal-fetal health.

Leptospira noguchii associated to reproductive disease in ruminants.

Leptospirosis is known to determine reproductive disorders on livestock, and Leptospira interrogans and Leptospira borgpetersenii are the most frequently reported species. Leptospira noguchii is an emerging pathogen, but its association with reproductive disease is unclear. We have detected L. noguchii as the agent of an outbreak with reproductive disorders in a Brazilian dairy goat flock. In the kidding season, five out of 10 Saanen had abortions in the final month of pregnancy and two newborn kids had acute clinical signs. After necropsy of three foetuses and one newborn kid, fragments of liver, lung and kidney were submitted to lipL32-PCR. It yielded positive results in at least one fragment from each animal. After, a nested secY-PCR, followed by sequencing, could identify L. noguchii, with 99-100% of identity with sequences obtained from cattle in the same region. For the first time, L. noguchii was detected in goats and, most importantly, the association of this leptospiral species with reproductive failures in ruminants has been demonstrated.

Immunohistochemical expression of HER - 2 and Ki - 67 in granulosa cell tumor in bitches.

Granulosa cell tumour, an ovarian neoplasm of stromal origin, is an important tumour related to oestrogenic dominance syndrome and cystic endometrial hyperplasia-pyometra complex. In order to analyse ovarian tumour´s malignant potential, immunohistochemical markers can be used, such as anti-HER2 and anti-Ki-67. The aim of this study was to evaluate the expression of immunohistochemical markers HER-2 and Ki-67 in granulosa cell tumour from bitches´ ovaries. In HER-2 immunomarker analysis using the HercepTest® method, most tumours were classified as 2+ (moderate labelling). Concerning Ki-67 immunomarker, only one case was described as having a high proliferative index. An association was found between immunostained cell percentage by anti-HER-2 antibodies and high pleomorphism, represented by the pattern of follicular/trabecular tumour arrangement. There was no correlation between anti-Ki-67 and anti-HER-2 antibody immunostaining intensities, probably due to only one case with a high Ki-67 index. With an effective protocol for HER-2 and Ki-67 immunohistochemical identification in granulosa cell tumours in bitches, it was possible to characterize this neoplasm proliferation profile.

Evaluation of Larval Therapy Compared to Antibiotic Therapy in the Treatment of Skin Wounds in Rabbits.

Larval therapy (LT) is a therapeutic modality that uses larvae of necrophagous flies for the treatment of wounds. The use of this therapy presents several benefits, due to the action of the larvae that remove necrotic tissue selectively, exercising antimicrobial action, and promoting healing. There are situations in which LT proves to be the only or the best alternative for the patient, such as wounds infected by multidrug-resistant microorganisms or when treatment difficulties may lead to an indication for amputation. The purpose of this study was to compare the efficiency of LT, using larvae of Chrysomya megacephala, with that of antibiotic therapy in the treatment of cutaneous wounds infected with Pseudomonas aeruginosa. Twenty-four rabbits were used to perform the experiment, distributed in four groups: group 1, induced wound without bacterial infection; group 2, induced wound with bacterial infection; group 3, induced wound with bacterial infection and antibiotic therapy; group 4, induced wound with bacterial infection and LT. The macroscopic, microscopic, and statistical analyses indicated that LT was as effective as antibiotic therapy in wound healing.

Esporotricose felina: um relato de caso de disseminação cutânea e sistêmica em gato negativo para FIV e FeLV / Feline sporotrichosis: a case report of cutaneous and systemic dissemination in cat negative for FIV and FeLV

A esporotricose é uma zoonose causada por fungos do gênero Sporothrix. Os gatos doentes têm importante potencial zoonótico e frequentemente revelam uma apresentação disseminada da doença. O objetivo deste relato de caso é descrever as características clínicas e anatomopatológicas de um caso de esporotricose felina refratária ao tratamento com apresentação clínica cutânea disseminada e sistêmica. Um felino macho de 3 anos de idade foi tratado para esporotricose com itraconazol e obteve resolução completa das lesões cutâneas. Porém, um ano após alta clínica, o animal apresentou aumento e ulceração da região nasal. Após cultura fúngica positiva para Sporothrix spp foi instituído tratamento com itraconazol 100mg associado ao iodeto de potássio 20mg por via oral diariamente e transcorrido 3 meses de tratamento, foi observada piora progressiva do sinais clínicos com disseminação de lesões para outras regiões do corpo. O animal foi submetido à eutanásia e encaminhado para necrópsia no Serviço de Anatomia Patológica da Faculdade de Veterinária da Universidade Federal Fluminense. Amostras da língua, pulmão, fígado, baço, rim, cérebro, linfonodo e pele foram coletadas para evidência de disseminação do agente fúngico e avaliação de alterações microscópicas. A coloração de metenamina de prata de Grocott foi utilizada para facilitar a visualização de leveduras sugestivas de Sporothrix spp

Sporotrichosis is a zoonosis caused by fungi of the genus Sporothrix. Sick cats have an significant zoonotic potential and often show a widespread presentation of the disease. The purpose of this case report is to describe the clinical and anatomopathological characteristics of a case of feline sporotrichosis refractory to treatment with disseminated and systemic cutaneous clinical presentation. A 3-year-old male feline was treated for sporotrichosis with itraconazole and achieved complete resolution of the skin lesions. However, one year after clinical discharge, the animal presented an increase and ulceration of the nasal region. After a positive fungal culture for Sporothrix spp, treatment with itraconazole 100mg associated with potassium iodide 20mg was instituted orally daily and after 3 months of treatment, a progressive worsening of the symptoms was observed with the spread of lesions to other regions of the body. The animal was euthanized and sent for necropsy at the Pathological Anatomy Service of the Veterinary Faculty of Universidade Federal Fluminense. Samples of the tongue, lung, liver, spleen, kidney, brain, lymph node, and skin were collected for evidence of spread of the fungal agent and evaluation of microscopic changes. Grocott silver methenamine staining was used to facilitate the visualization of yeasts suggestive of Sporothrix spp in histological sections. Yeasts were visualized in samples of skin, tongue, lymph node, kidney, liver, spleen, and brain. In the present report, the spread of Sporothrix spp to different organs signals the need for a thorough investigation of severe cases of feline sporotrichosis for the proper treatment.

Esporotricose felina: um relato de caso de disseminação cutânea e sistêmica em gato negativo para FIV e FeLV / Feline sporotrichosis: a case report of cutaneous and systemic dissemination in cat negative for FIV and FeLV

A esporotricose é uma zoonose causada por fungos do gênero Sporothrix. Os gatos doentes têm importante potencial zoonótico e frequentemente revelam uma apresentação disseminada da doença. O objetivo deste relato de caso é descrever as características clínicas e anatomopatológicas de um caso de esporotricose felina refratária ao tratamento com apresentação clínica cutânea disseminada e sistêmica. Um felino macho de 3 anos de idade foi tratado para esporotricose com itraconazol e obteve resolução completa das lesões cutâneas. Porém, um ano após alta clínica, o animal apresentou aumento e ulceração da região nasal. Após cultura fúngica positiva para Sporothrix spp foi instituído tratamento com itraconazol 100mg associado ao iodeto de potássio 20mg por via oral diariamente e transcorrido 3 meses de tratamento, foi observada piora progressiva do sinais clínicos com disseminação de lesões para outras regiões do corpo. O animal foi submetido à eutanásia e encaminhado para necrópsia no Serviço de Anatomia Patológica da Faculdade de Veterinária da Universidade Federal Fluminense. Amostras da língua, pulmão, fígado, baço, rim, cérebro, linfonodo e pele foram coletadas para evidência de disseminação do agente fúngico e avaliação de alterações microscópicas. A coloração de metenamina de prata de Grocott foi utilizada para facilitar a visualização de leveduras sugestivas de Sporothrix spp nos cortes histológicos. Leveduras foram visualizadas em amostras de pele, língua, linfonodo, rim, fígado, baço e cérebro. No presente relato a disseminação do Sporothrixspp para diversos órgãos sinaliza a necessidade de uma minuciosa investigação dos casos graves de esporotricose felina para o tratamento adequado.

Sporotrichosis is a zoonosis caused by fungi of the genus Sporothrix. Sick cats have an significant zoonotic potential and often show a widespread presentation of the disease. The purpose of this case report is to describe the clinical and anatomopathological characteristics of a case of feline sporotrichosis refractory to treatment with disseminated and systemic cutaneous clinical presentation. A 3-year-old male feline was treated for sporotrichosis with itraconazole and achieved complete resolution of the skin lesions. However, one year after clinical discharge, the animal presented an increase and ulceration of the nasal region. After a positive fungal culture for Sporothrix spp, treatment with itraconazole 100mg associated with potassium iodide 20mg was instituted orally daily and after 3 months of treatment, a progressive worsening of the symptoms was observed with the spread of lesions to other regions of the body. The animal was euthanized and sent for necropsy at the Pathological Anatomy Service of the Veterinary Faculty of Universidade Federal Fluminense. Samples of the tongue, lung, liver, spleen, kidney, brain, lymph node, and skin were collected for evidence of spread of the fungal agent and evaluation of microscopic changes. Grocott silver methenamine staining was used to facilitate the visualization of yeasts suggestive of Sporothrix spp in histological sections. Yeasts were visualized in samples of skin, tongue, lymph node, kidney, liver, spleen, and brain. In the present report, the spread of Sporothrix spp to different organs signals the need for a thorough investigation of severe cases of feline sporotrichosis for the proper treatment.

The sensitivity of Demodex canis (Acari: Demodicidae) to the essential oil of Melaleuca alternifolia - an in vitro study.

The essential oil of the Melaleuca alternifolia (Maiden & Betche) (tea tree oil) has been effective in previous studies, in the treatment of infestation by Demodex mites in humans. The present study aimed at evaluating the in vitro acaricidal effect of this herbal medicine on Demodex canis. For the parasitological examination, samples were collected from a dog's skin and examined using optical microscopy. Only samples with intact mites and with evident movement of chelicerae and tarsi were selected. Twenty-one samples were tested with the oil, in seven different concentrations: 100%; 50%; 25%; 12.5%; 6.25%; 5.0% and 3.13%. Three samples were tested with the positive control amitraz, and three with the negative control neutral shampoo. The interval between the time the solution was added and the moment the movement of the last mite ceased defined the survival time in the sample. By comparing the times at different concentrations and controls, the results showed that the higher the concentration of the oil, the more quickly its lethal effect occurred, and that the survival times in the controls were longer than in the different concentrations of melaleuca oil.

Histopathological study of canine sebaceous tumors and their association with PCNA expression by immunohistochemistry / Estudo histopatológico de tumores sebáceos caninos e sua associação com a expressão de PCNA por imuno-histoquímica

Sebaceous tumors are common in dogs and include benign and malignant lesions. The increase in immunohistochemical evaluation of sebaceous tumors aggregates information regarding the origin and degree of malignancy of the lesions. The objective of this study was to evaluate PCNA immunohistochemical expression of  sebaceous tumors in dogs. Sixty-one samples include normal skin and sebaceous tumors were selected from dogs of various breeds and ages, no gender predilection, sent to the Veterinary Pathology Service of Universidade Federal Fluminense, Niterói/RJ, Brazil. Samples passed through histological processing, routine staining and immunostaining from PCNA. Descriptive statistical analysis, Wilcoxon-Mann-Whitney and Fishers exact test were performed. The mean age of the affected animals was 10.56 years. There was no sexual predilection. Breeds more frequently affected were: Poodles, mixed-breed dogs and Cocker Spaniels. Most of the tumors were neoplasms (67.27%), and 75.67% of those were benign. Sebaceous adenoma was the most frequent neoplasm (56.75%). PCNA immunoexpression was present in hyperplasia, benign and malignant tumors. No previous studies were found using PCNA antibody in sebaceous tumors of dogs. Thus, more studies are needed to provide greater clarity regarding the role of these markers on normal skin and sebaceous tumors of dogs, as well as their use as prognos

Tumores sebáceos são comuns em cães. Tais tumores incluem lesões benignas e malignas. A avaliação imunohistoquímica desses tumores pode agregar informações sobre a origem e o grau de malignidade das lesões. Para este fim, sessenta e uma amostras, incluindo pele normal e tumores sebáceos foram selecionadas de cães de várias raças e idades, sem predileção por sexo, do arquivo do Serviço de Patologia Veterinária da Universidade Federal Fluminense, Niterói/RJ, Brasil. As amostras passaram por processamento histológico, coloração de rotina e imuno-histoquímica com anti-PCNA (proliferating cell nuclear antigen). Foram realizadas análises estatísticas descritivas além dos testes de Wilcoxon-Mann-Whitney para comparar a distribuição da marcação de anti-PCNA entre grupos de variáveis. Para variáveis com mais de dois grupos, aplicou-se a Análise de Variância (ANOVA). A idade média dos animais afetados foi de 10.56 anos. As raças mais afetadas foram Caniches e Cocker Spaniel, e ainda animais sem raça definida. Houve imunomarcação de PCNA em tumores benignos, malignos, e ainda em lesões hiperplásicas com intensidade variada. A maioria dos tumores eram neoplásicos representando 67.92% do total; destes, 75.00% eram benignos. O adenoma sebáceo foi a neoplasia mais frequente (37.74%). Não foram encontradas diferenças significativas nas distribuições de anti-PCNA entre os grupos das variáveis sexo, idade, status reprodutivo, localização e tamanho do tumor e diagnóstico histopatológico. Embora não haja estudos com anti-PCNA em tumores sebáceos caninos, numerosas publicações apontam seu valor preditivo em outras neoplasias. Com isso, a finalidade deste estudo foi avaliar a expressão de anti-PCNA em tumores sebáceos caninos e sua possível associação com a malignidade das lesões.

Histopathological study of canine sebaceous tumors and their association with PCNA expression by immunohistochemistry / Estudo histopatológico de tumores sebáceos caninos e sua associação com a expressão de PCNA por imuno-histoquímica

Sebaceous tumors are common in dogs. These tumors include both benign and malignant lesions. Immunohistochemical evaluation of these tumors can aggregate information regarding the origin and degree of malignancy of the lesions. Focusing on this matter, sixty-one samples including normal skin and sebaceous tumors were selected from dogs of various breeds and ages, with no predilection for sex, from the archive of Veterinary Pathology Service of Federal Fluminense University, Niterói/RJ, Brazil. The samples underwent to histological processing, routine staining and immunohistochemistry with anti-PCNA (proliferating cell nuclear antigen). Descriptive statistical analysis was performed, the Wilcoxon-Mann-Whitney test was used to compare the distribution of anti-PCNA labelling in different groups of variables. In case there were more than two groups, the Analysis of Variance (ANOVA) test was performed. The mean age of the affected animals was 10.56 years. The most affected breeds were Caniches and Cocker Spaniels, as well as mixed breed animals. There was immunostaining of PCNA in both benign and malignant tumors, as well as in hyperplasic lesions with varying intensity. Most of the tumors were neoplasms which represented 67.27% of the total sample; within these, 75.00% were benign. The most frequent neoplasm was sebaceous adenoma (37.74%). Results indicated no statistical difference in the distribution of anti-PCNA labelling between the groups of sex, age, reproductive status, localization, size of tumor, and histopathological diagnosis. Although there are not many studies analyzing anti-PCNA labelling in sebaceous tumors, several of them pointed out to the predictive value in other neoplasms. With this matter in mind, we intended to evaluate the expression of anti-PCNA in canine sebaceous tumor and a possible association with the malignancy of the lesions.

Tumores sebáceos são comuns em cães. Tais tumores incluem lesões benignas e malignas. A avaliação imunohistoquímica desses tumores pode agregar informações sobre a origem e o grau de malignidade das lesões. Para este fim, sessenta e uma amostras, incluindo pele normal e tumores sebáceos foram selecionadas de cães de várias raças e idades, sem predileção por sexo, do arquivo do Serviço de Patologia Veterinária da Universidade Federal Fluminense, Niterói/RJ, Brasil. As amostras passaram por processamento histológico, coloração de rotina e imuno-histoquímica com anti-PCNA (proliferating cell nuclear antigen). Foram realizadas análises estatísticas descritivas além dos testes de Wilcoxon-Mann-Whitney para comparar a distribuição da marcação de anti-PCNA entre grupos de variáveis. Para variáveis com mais de dois grupos, aplicou-se a Análise de Variância (ANOVA). A idade média dos animais afetados foi de 10.56 anos. As raças mais afetadas foram Caniches e Cocker Spaniel, e ainda animais sem raça definida. Houve imunomarcação de PCNA em tumores benignos, malignos, e ainda em lesões hiperplásicas com intensidade variada. A maioria dos tumores eram neoplásicos representando 67.92% do total; destes, 75.00% eram benignos. O adenoma sebáceo foi a neoplasia mais frequente (37.74%). Não foram encontradas diferenças significativas nas distribuições de anti-PCNA entre os grupos das variáveis sexo, idade, status reprodutivo, localização e tamanho do tumor e diagnóstico histopatológico. Embora não haja estudos com anti-PCNA em tumores sebáceos caninos, numerosas publicações apontam seu valor preditivo em outras neoplasias. Com isso, a finalidade deste estudo foi avaliar a expressão de anti-PCNA em tumores sebáceos caninos e sua possível associação com a malignidade das lesões.

Gastric lesions in free-living sea turtles: An underestimated disease that reflects the health of the ecosystem.

Free-living marine turtles are constantly exposed to aggression factors and the gastrointestinal tract is one of the main gateways of entry. The objective of this study was to identify, and describe the anatomopathological alterations in the stomach of free-living marine turtles found dead on the beaches of the Microrregião dos Lagos, Rio de Janeiro, Brazil. Twenty-two sea turtles were necropsied, and stomach fragments were collected, fixed, and processed routinely. The presence of gastritis, parasitism, and adaptative morphological alteration of the cells were evaluated in a microscopic analysis. Descriptive statistics and Fisher's exact test were performed. Of the samples, 59.1% had stomach hyperemia. Microscopically, gastritis was found in 86.4% of cases, parasitism in 72.7%, and adaptive morphological alteration in 59.1%. There was an association between the presence of cellular adaptive morphological alteration and chronic inflammation. This the first report to describe the adaptive morphological changes observed in the stomach cells. The chronicity of the lesions was due to continuous aggressions to the tissue, with parasitism, garbage ingestion, and environmental pollutants as possible causes. The results obtained in this study demonstrate that the chronicity of the stomach lesions is due to continuous aggressions to this tissue, and the irritating factors have environmental origin, such as parasites, garbage, and toxic pollutants, including heavy metals, which are ingested by free-living sea turtles. This article demonstrates that stomach injuries in free-living marine turtles are frequent, severe, and possibly underdiagnosed; these lesions reflect the diseased ecosystem in which those animals live.

Epidermal growth factor receptor 2 immunoexpression in gastric cells of domestic cats with H. heilmannii infection.

The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate.

Histopathological findings in the early diagnosis of granulosa cell tumour in bitches.

Granulosa cell tumour (GCT) is a majorly observed ovarian tumour in female dogs. It is essential to diagnose GCT in its initial phase before any symptoms occur, as histological and physiological differences may be observed based on the evolution of this neoplasia. This study aimed to analyse the anatomic histopathology of GCT in its initial stage, with findings of ovaries not yet with the suspicion of neoplasms in the Canis familiaris. A sample including 55 ovaries presented GCT in 40 female dogs. The histopathological analysis was performed considering the intensity of pleomorphism, vascularization and inflammatory infiltrate. Furthermore, we evaluated the mitoses count in 10 fields using 40× magnification. Out of the 40 animals evaluated, 62.5% (25/40) presented the tumour in only one ovary. The Call-Exner corpuscle was present in 65% (26/40) of the cases. The follicular histological pattern was present in 52.5% (21/40) of the animals. The presence of the Call-Exner bodies and the degree of tumour cell pleomorphism (p = 0.033) were associated. Moreover, the degree of vascularization and the intensity of the inflammatory infiltrate were also related (p = 0.001). In addition, there was a positive relationship between the increase in pleomorphism and the mean age of the animals (p = 0.044). This study confirmed that the appearance of this tumour may precede any clinical symptomatology. In this study, the most frequent histopathological pattern was the follicular. The characteristics of the granulosa cell tumour diagnosed early were poorly pleomorphic cells, low mitotic index and presence of Call-Exner body.

Vimentin, osteocalcin and osteonectin expression in canine primary bone tumors: diagnostic and prognostic implications.

Canine primary bone tumors have a plastic radiographic image, demanding histopathological confirmation. Bone tumors are characterized by the type and amount of extracellular matrix produced what cannot be easily recognized, especially in biopsy samples. Identifying cellular markers that could aid diagnosis has supported various studies in oncological pathology. This study aimed to evaluate 22 canine primary bone neoplasms, establishing their histopathological diagnosis and evaluated vimentin, osteonectin and osteocalcin expression and their implication in diagnosis and prognosis. There were 12 productive osteoblastic osteosarcomas, six minimally productive osteoblastic osteosarcoma, two chondrosarcomas, one fibrosarcoma and one hemangiosarcoma. Immunostaining was cytoplasmatic in all cases, with average percentage of 87.9% for vimentin, 98.0% for osteonectin and 99.9% for osteocalcin. In this last case, only osteosarcomas were considered. Intensity was higher in vimentin labeling (+++), followed by osteonectin (++) and osteocalcin (+). One osteosarcoma showed negative immunostaining for vimentin and of samples submitted to anti-osteocalcin immunostaining, three osteosarcomas and one fibrosarcoma had negative staining. Besides identifying mesenchymal origin, vimentin elevated expression in canine bone tumors can be related to epithelial-mesenchymal transition, leading to more aggressive tumoral phenotypes and metastasis development. Similarly, high osteonectin expression is implicated in neoplastic cell invasion and is also related to metastasis spread. Decreased osteocalcin expression was found in some osteosarcoma samples and can be related to poor prognosis, as in human osteosarcomas. Our findings suggest that vimentin, osteonectin and osteocalcin not only aid diagnosis but can be related to prognosis in canine primary bone tumors, especially osteosarcomas and its osteoblastic subtype.

Muscle regeneration through therapy with estromal stem cells in injury of infraespinhosus muscle of sheep.

PURPOSE: To evaluate the effects of rotator cuff muscle regeneration in sheep and establish an experimental model for the use of autologous stem cells as a treatment option for tendon injuries. METHODS: Infrared muscle tenotomies and Penrose drain implantation were performed on 12 shoulders of six clinically healthy adult sheep. After 60 days, the tendons were submitted to tissue repair, drainage removal, and divided into two groups according to the use of autologous stromal stem cells for treatment. Muscle regeneration was performed by biopsy on days 14 and 34 after repair. RESULTS: The treatment group with cell therapy showed neovascularization and expressive regeneration. Complete regeneration of the muscle pattern did not occur in any sample although some muscle gain was obtained in the group 1 samples at 34 days after repair and introduction of stem cells. Fatty infiltration of these samples from group 1 at 34 days was less intense than that in samples from group 2 at 34 days after repair without the introduction of autologous precursor cells. CONCLUSION: The sheep proved to be a good experimental model to assist in the development of research on muscle regeneration and the autologous manipulation of stem cells as a therapeutic option.

Muscle regeneration through therapy with estromal stem cells in injury of infraespinhosus muscle of sheep

Abstract Purpose: To evaluate the effects of rotator cuff muscle regeneration in sheep and establish an experimental model for the use of autologous stem cells as a treatment option for tendon injuries. Methods: Infrared muscle tenotomies and Penrose drain implantation were performed on 12 shoulders of six clinically healthy adult sheep. After 60 days, the tendons were submitted to tissue repair, drainage removal, and divided into two groups according to the use of autologous stromal stem cells for treatment. Muscle regeneration was performed by biopsy on days 14 and 34 after repair. Results: The treatment group with cell therapy showed neovascularization and expressive regeneration. Complete regeneration of the muscle pattern did not occur in any sample although some muscle gain was obtained in the group 1 samples at 34 days after repair and introduction of stem cells. Fatty infiltration of these samples from group 1 at 34 days was less intense than that in samples from group 2 at 34 days after repair without the introduction of autologous precursor cells. Conclusion: The sheep proved to be a good experimental model to assist in the development of research on muscle regeneration and the autologous manipulation of stem cells as a therapeutic option.

Validation of a low-cost modified technique for constructing tissue microarrays for canine mammary tumor analysis.

Compared with conventional histological paraffin blocks, tissue microarray (TMA) represents a "high-throughput tool" that provides rapid results, a time- and cost-effective approach and simultaneous investigation of several tissue samples under the same conditions. Given the large number of cases of dogs affected with mammary tumors, the complexity of these tumors and their similarity with breast cancer in women, this study aimed to validate a low-cost modified method to construct TMAs for canine mammary tumor analysis using immunomarkers. Carcinoma cases were selected from canine mammary carcinomas in mixed tumors (CMT) because this tumor type is the most heterogeneous among the histopathological types of mammary tumors observed in female dogs. Through a histopathological examination, tumor representativity was compared between conventional sections and histological sections obtained from the TMA block; both were stained with hematoxylin and eosin. An immunohistochemistry analysis was performed to compare the percentages of immunoreactive cells obtained in whole tissue sections versus those obtained from sections from the TMA block. Streptavidin-biotin peroxidase complex and anti-PCNA, anti-vimentin and anti-pancytokeratin antibodies were used. Statistical analysis consisted of the nonparametric Friedman's test (p≤0.05) and descriptive statistical analysis. Histopathological analysis showed tumor representativity in all TMA cores selected for the study. There was no difference between the immunohistochemical analysis of mammary tumors using conventional histological sections or sections obtained from a single 1-mm-diameter TMA core, regardless of the marker used: PCNA (p=0.279), pancytokeratin (p=0.243) and vimentin (p=0.967). The results did not change even when the means of any number of cores were compared among each other and with the conventional histological section: PCNA (p=0.413), pancytokeratin (p=0.177) and vimentin (p=1.0). Therefore, this study validates the use of a low-cost and modified TMA construction technique proposed by Pires et al. for canine mammary tumor analysis.

Leukocyte infiltration and anti-myeloperoxidase immunoreactivity in granulocytes of the mucosa and submucosa of the large intestine of horses submitted to dietetic starch overload / Infiltração de leucócitos e imunorreatividade antimieloperoxidase em granulócitos da mucosa e submucosa do intestino grosso de equinos submetidos à sobrecarga dietética com amido

This study was carried out to evaluate leukocyte infiltration and anti-myeloperoxidase immunoreactivity in granulocytesof the mucosa and submucosa of the large intestine of horses submitted to dietetic starch overload. Eight adult horseswere allocated randomly in three treatments: Treatment I (Control) (n = 2), animals euthanized without starch overload;and Treatments II (n = 3) and III (n = 3), animals undergoing starch overload, with gastric infusion of 17.6 g starch perkg of body weight, euthanized after 24 and 36 hours, respectively. Only afflux of neutrophils in the intestinal mucosa andsubmucosa blood vessels (leukocyte stasis) was observed. Eosinophils were the predominant cells in the mucosa andsubmucosa in all horses, independent of dietetic overload, with infiltration grade from mild to moderate. Lymphocyteinfiltration was also observed in all horses, but with lower intensity when compared to eosinophils. Congestion, edemaand dilatation of lymphatic vessels were the main circulatory alterations observed, with more intensity in the submucosa.Higher immunoreactivity to the anti-myeloperoxidase antibodies was observed in the mucosa and submucosa of horses36 hours after overload. Horses submitted to dietetic starch overload showed intestinal inflammatory response withprevalence of eosinophils, leukocyte stasis and circulatory alterations, varying from discreet to moderate

Este estudo teve como objetivo avaliar a infiltração de leucócitos e a imunorreatividade antimieloperoxidase emgranulócitos da mucosa e submucosa do intestino grosso de equinos submetidos à sobrecarga dietética com amido.Oito equinos adultos foram distribuídos aleatoriamente em três tratamentos: Tratamento I (Controle) (n = 2), equinoseutanasiados sem sobrecarga com amido; Tratamento II (n = 3) e III (n = 3), equinos submetidos à sobrecarga comamido, com infusão gástrica de 17,6 g de amido/kg de peso vivo e eutanasiados após 24 e 36 horas, respectivamente.Observou-se apenas afluxo de neutrófilos (leucocitoestase) nos vasos sanguíneos da mucosa e submucosa intestinal.Eosinófilos foram as células predominantes na mucosa e submucosa em todos os equinos, independente da sobrecargadietética, com grau de infiltração de leve a moderada. Infiltração por linfócitos também foi observado em todos osequinos, porém com menor intensidade quando comparado aos eosinófilos. Congestão, edema e dilatação de vasoslinfáticos foram as principais alterações circulatórias observadas, com maior intensidade na submucosa. Maiorimunorreatividade para anticorpos antimieloperoxidase foi observado na mucosa e submucosa dos equinos 36 horasapós a sobrecarga. Equinos submetidos à sobrecarga dietética com amido apresentam resposta inflamatória intestinalcom predominância de eosinófilos, leucocitoestase e alterações circulatórias variando de discreta a moderada